Lubricant



li aiented Bee. l7, lg ifi.

s ray-as grasses MEN? or No Drawing. Application Eanuary is, 1987, Serial No. 121,167

23 Claims.

This invention relates primarily to modified mineral lubricating oils, the general object of the invention being to supply to lubricating oils oiliness and stabilizing constituents, capable of imparting extreme pressure characteristics and also of overcoming the deposition of gums, resins and varnish-like materials upon and aboutthe valves and rings of internal combustion engines, and preventing the sticking of rings and valves especially in engines of the Diesel type where operating conditions are in general rather severe.

In the case of many lubricating oils there has in the past been a strong tendency toward the development of resinous and similar deposits about valves and rings of internal combustion engines due principally to the lubricating oil used, although in part to the fuel in some instances. These objectionable deposits, which often result in such sticking of valves and rings as to interiere materially with engine operation, are perhaps more often found in the case of Diesel engines and engines operating under similar severe conditions. I have found that the tendency of mineral lubricat'mg oils to deposit gums, resins and varnish-like materials can be largely overcome by the addition of comparatively small quantities of certain types of oil-soluble metal soaps, particularly soaps of halogenated fatty acids, halogenated naphthenic acids, and halogenated synthetic petroleum acids such as those produced by oxidation of petroleum fractions to .yield oil-soluble synthetic acids of fairly high molecular weight. Such oil-soluble soaps preferably are those of the alkali earth metals and heavy metals in general, for example calcium, magnesium, aluminum, lead, iron and zinc soaps. Other possibilities for soaps of such acids are found in sodium, potassium, copper, cobalt and nickel soaps when oil-soluble.

Broadly stated, the invention resides in a lubricating oil otherwise possessing the properties of forming gummy, resinous and varnish-like deposits upon and about the valves and piston rings of internal combustion engines, containing a small quantity, but suficient however to avoid substantial deposit of such objectionable materials, of a metal soap of acids of the type of halogenated fatty acids and halogenated synthetic petroleum acids of relatively high molecular weight, i. e., having not less than about ten carbon atoms. For these purposes the soaps are to be employed ordinarily to the extent of about 1%, for the reason that. substantially greater amounts of soaps tend ordinarily to thicken the 5:. oils undesirably and without benefit. whereas small quantities, ior example about /2% or less, ordinarily do not impart sufficient stabilizing capacity to avoid or overcome depositionof gums, resins and the like. These oils also possess improved iilm strength or load-carrying capacity. 5

' The invention resides further in oil containing such soaps as above indicated for the indicated purpose wherein the oil itself is especially adapted to the severe uses encountered in Diesel engines and the like. Such an oil preferably is a naph- 10 thenic base oil which in itself affords some sol vent characteristics for gums, resins,.and varnishes. On the other hand, highly refined, highly parafiinic oils may be employed at least for some uses, as may less heavily refined highly parafinic 15 oil, such as ordinary grades of Pennsylvania oils.

I have also discovered that oil soluble metal or organic base soaps of non-halogenated acids of I the types above described may be combined as one component of a double-component addition ma- 20 teriai with any type of oiliness agent as a second component. Such a second constituent may be methyl aa' dichloro-stearate, other ciliness agent of the type produced from other alcohols such as ethyl and amyl alcohol and from other acids 25 such as oleic, palmitic and similar acids, chlorinated paraifin, sulfurlzed lard oil, chlorinated diphenyl oxide, sulfurized or halogenated fatty acids of the types herein indicated, halogenated or sulfurized synthetic petroleum acids such as 30 have been described, tricresyl phosphate, and in general all other types of olliness agents.

Therefore the invention may be also stated as extending to the use in mineral lubricating oils of an oil-soluble soap constituent combined with 5 an oiliness or illm-strength-improving element or constituent, such as one or more sulfur or chlorine atoms or phosphorous groups and the like, contained either in the soap itself, or contained in a second additive component when the 40 soap itself does not contain such an oillness or film-improving element or constituent. in this respect, the invention also includes soaps made with organic bases such as triethanolamine, uinoline, nitrogen bases from petroleum and the 45 like. Such organic base soaps are to be used as substitutes for said oil-soluble metal soap when that soap is not chlorinated (or similarly modiiied) and is required to be used in a two-component additive material. When such an organic base soap is chlorinated it may be used as a single component additive as a substitute for the oil-soluble metal chlorinated soaps (or similar soaps) described. Soaps appropriate for this purpose are represented by triethanolamine naphthenate, triethanolamine chloro-naphthenate, triethanolamine chlorinated or sulfurized fatty acid soaps and other similar soaps of acids herein mentioned.

In practicing the present invention, any otherwise satisfactory mineral lubricating oil is selected. As above indicated, this is preferably a naphthenic base or Western type oil, especially where such an oil is to be used for Diesel engine lubrication. On the other hand, where conditions are less severe, paraflinic oils may be employed.

According to one form of the invention, I add to such an oil approximately 1% of a soap capable of preventing the formation and/or accumulation of gums, resins and varnishes upon and about rings and valves of internal combustion engines. While the amount of such soaps may be varied between about 0.5 or 0.6% and about 2%, I prefer to use approximately 1% or between about 0.8% and 1.25%, inasmuch as such proportions have so far proved to be most beneficial.

The soaps which I have found to be highly satisfactory for these purposes are especially the alkali earth metal soaps of halogenated fatty acids and of halogenated high molecular weight synthetic petroleum acids. For example the calcium soap of chlorinated stearic acid has been found highly eflicient. Similarly, the calcium soap of chlorinated oleic acid is very desirable. Both the calcium dichloro-stearate and the calcium dichloro-oleate function adequately in the proportions above indicated to yield a highly satisfactory oil for Diesel engine or similar uses. the performance of the two oils being much the same,- although the two chlorine atoms are attached to the 9th and 10th carbon by direct addition in the case of the chlorinated oleic acid, whereas they are attached to the alpha carbon byi substitution in the case of the saturated stearic acid. The chlorine content of these two materials is about 20% based on'the acid, although it may be in the case of the chlorinated stearic acid that part of the chlorine is attached to the betacarbon or the gamma carbon or elsewhere. Such chlorine contents lower the melting points of the acids and render both the acids and their indicated soaps readily compatible with the lubricating oil, yielding the freely oil-soluble soaps indicated. In addition to the calcium soaps, other alkali earth metal soaps such as magnesium soaps may be employed, as may other metal soaps like aluminum dichloro-oleate and stearate. Again, soaps of other chlorinated fatty acids having a minimum of about ten carbons to insure a sufllciently high molecular weight and boiling point may be employed. Corresponding soaps of chlorinated synthetic petroleum acids likewise may be employed. These acids themselves are well known on the market, and

are frequently produced by oxidation, cataiyticaily and otherwise, of petroleum products, particularly fractions in the light and intermediate lubricating 'oil ranges, oxidation being a 'convenient means for the formation of the acids. These acids are recovered by precipitation as soaps with subsequent cracking out by the use of strong mineral acids to yield the purified acids. These procedures are generally well understood and need not be here described. These acids may be more or less readily chlorinated or otherwise halogenated merely by passage of the halogen gas through the acids to effect the desired sub-' stitution and/or addition; followed by adequate neutralization and washing. The soaps of such halogenated acids are then readily formed by saponification with suitable metal salts, hydroxides or oxides in the same way that fatty acid soaps are formed, as well understood in the industry.

In addition to the indicated metal soaps of various halogenated fatty acids such as oleic, linoleic, stearic, palmitic, the coconut fatty acids and the like, and theindicated soaps of halogenated naphthenic acids and halogenated synthetic petroleum acid, I may also use corresponding oil-soluble sulfurized or phosphorous-bearing soaps of such acids of sufficiently high molecular weight as herein indicated. Also, I contemplate the use of special soaps, such as a lead soap of highly chlorinated organic acids, particularly naphthenic acids, as components in extreme pressure gear oils and the like. Thus, the oil soluble metal soaps of the chlorinated or otherwise halogenated naphthenic acids, corresponding sulfurized acids, and halogenated and sulfurized lard oils and fatty acids, and the like, are included.

According to another form of the invention, I have foundv it practicable to use a two-component additive material, one of which is a non-halogenated or sulfurized soap for the purpose of prevention of deposition of gums and resins and the like, and the other of which is an oiliness constituent which imparts high load carrying capacity. Whereas, in the case of a single component, calcium dichioro-stearate for example, both the oiliness element and the element for overcoming deposition of gums and resins are contained in one compound, in this modification of the invention the soap which largely overcomes deposition of gums and resins does not contain combined therein an agent for improving oiliness and film strength, such as sulfur, a halogen, phosphorus, or the like, but the soap is employed in conjunction with a second component of which methyl dichloro-stearate is a good example, such second agent imparting the desired oiliness and increased load carrying capacity. For example, I may employ approximately 1% of a calcium soap of palm oil, or coconut oil, or oleic acid, stearic acid'or the like, or other disclosed acid, together with about 0.5% to 1.0% of methyl dichlor-stearate as the oiliness agent to increase fllm st engthand load carrying capacity. Other oilinem agents of this generaltype may be substituted such as those produced from ethyl, amyl or other alcohols and from oleic, palmitic and other acids, the agent containing one of the halogens such as chlorine, bromine, fluorine or iodine. In addition to halogenated ester types, other types of oiliness agents, such as chlorinated paraflin, sulfurized lard oil, suifurized fatty acids, sulfurized acids of the other types herein disclosed, chlorinated diphenyl oxide, tricresyl phosphate and kindred phosphorous compounds, and the like may be employed. In this manner the oiliness element such as chlorine, sulfur, phosphorous, or the like, isobtained through the medium of an agent other than the soap.

Similarly, I may use organic bases in preparing soaps for the use of the present invention.

- Such bases are represented by triethanolamine, quinoline bases, nitrogen bases from petroleum and the like. Where the triethanolamine soap is to be usedas one of the components of a twocomponent additive material, the acids would not generally contain an oiliness element such as chlorine, sulfur or the like. Such acids may be naphthenic acids, fatty acids containing a minimum of about 10 carbon atoms, synthetic petroleum acids as from oxidation of paraflin waxes and refined petroleum oils and all other types of acids herein mentioned. When the organic base soap, such as a triethanolamine soap, is to be used as a single component additive, then the acid radical will contain the oiliness agent such as chlorine, sulfur, phosphorous, a phenyl group or other suitable substituent. Soaps of this character will be used in percentages similar to those employed with other soaps.

In all aspects of the present invention, it will of course be obvious that in the case of chlorinated or sulfurized or similar materials that either the acids employed may first be chlorinated or otherwise treated, or the soaps after their formation may be so chlorinated, sulfurized, or otherwise modified, and the materials produced by both methods are intended to be included when acids and soaps are mentioned herein.

With respect to the synthetic petroleum acids, paraffin acids and the like such as produced by oxidation as herein mentioned, as distinguished from naphthenic acids, attention is called to the fact that these acids are of different character from naphthenic acids and present a vastly greater degree of oiliness properties than do the naphthenic acids and are in most instances to be preferred to naphthenic acids or any other naturally occurring petroleum acid such as obtained from petroleum distillates. The synthetic petroleum and paraflin acids mentioned may be produced by oxidation as well understood in the art or otherwise. a

Soaps of the indicated nature when added to lubricating oils are stable in use, and when employed in the indicated proportions do not appreciably affect the fluidity of the oils for lubrication purposes. The amount of soap to be added to the oil, as is evident from the above disclosure, is that quantity necessary to effectively avoid substantial deposit of gummy, resinous and varnishlike materials whereby to overcome ring and valve sticking in internal combustion engines including engines of the Diesel type. At the same time tendencies in fuel used with the engines to deposit similar or other gummy, resinous, varnish-like o constituents which tend to cause ring and valve sticking, are likewise overcome by the use of such amount of the indicated type of soap. As has been indicated, this amount is ordinarily in the order of about 1%. Besides an ordinary 55 range between about 0.5% and 2% as previously indicated, there may be instances where as little as 0.1% may be used, and on the other hand larger amounts extending up to possibly as high as 5% may be desirable undersome conditions,

for example where high temperatures are encountered. In other words, varying conditions can require wider ranges.

While the invention has been indicated as particularly applicable to mineral lubricating oils, it

5 may also be extended to fatty lubricating oils and the like.

It is to be understood that the above disclosures are furnished as being illustrative of the present invention, and that they are not to be taken as 70 limiting beyond the requirements of the prior art and as indicated by the appended claims.

I claim:

1. A mineral lubricating oil normally liquid for internal combustion engines containing a small 75 quantity in the order of 1.25% of freely oil-soluble metal salt of a chlorinated fatty acid sufiicient to overcome ring and valve sticking tendencies in internal combustion engines, without appreciably increasing the viscosity of the original lubricating oil and without imparting grease-like characteristics to the oil.

2. A lubricating oil containing a metal soap of a chlorinated fatty acid in a small quantity in the order of one to two percent and suflicient only approximately to avoid substantial deposit of gums, resins and varnish-like materials upon valves and rings of severe service internal combustion engines, without appreciably increasing the viscosity of the original lubricating oil and without imparting grease-like characteristics to v the oil.

tity between about /2% and 2% of a metal soapof a petroleum acid containing an element from the class: halogens, sulfur and phosphorous.

7. A mineral lubricating oil containing a small quantity in the order of about to 2% of an oil-soluble metal soap of a halogenated naphthenic acid.

8. A Diesel engine lubricating oil comprising as primary ingredients a mineral lubricating oil and between about 1% and 2% of calcium chlorostearates corresponding in chlorine content approximately to calcium dichloro-stearates.

9. A lubricating oil which is normally freely liquid comprising naphthenic base mineral lubricating oil containing a small proportion between about 1% and 2% of freely oil-soluble metal soap of saponifiable organic acid having at least ten carbon atoms to the molecule, in quantity sufflcient to overcome ring sticking and deposit of gummy and varnish-like materials in severe service internal combustion engines without appreciable increase in the viscosity of the original oil and without imparting grease-like characterstics to the oil, the soap having chemically combined therewith a film strength constituent in the form of chlorine. v

10. A Diesel engine lubricating oil comprising naphthenic base mineral lubricating oil and between about 1% and about 2% of an oil-soluble metal soap not appreciably increasing'the viscosity of the original oil nor imparting greaselike characteristics and containing a chemically combined film strength element of the class consisting of halogens, sulfur and phosphorous.

11. A lubricating oil which is normally freely liquid comprising naphthenic base mineral lubricating oil containing a small proportion between about 1% and 2% ofoil-soluble calcium soap of a fatty acid having at least 10 carbon atoms to the molecule and containing chlorine corresponding generally with dichloro soap, the proportion of soap being sumcient to overcome ring sticking and deposition of gummy and varnish-like materials in severe service internal combustion engines without appreciable increase in the viscosity of the original oil and without imparting greaselike characteristics to the oil.

12. A normally liquid lubricating oil for internal combustion engines comprising a mineral lubricating oil of lubricating viscosity ranges containing between /z% and less than 2% of freely oil-soluble soap of an organic acid having at least about ten carbon atoms per molecule and combined with a film-strength-increasing agent of the class consisting of the halogens, sulfur and phosphorus, the soap being present in amount suflicient to overcome substantially the deposit of gummy and varnish-like materials in severe service internal combustion engines without pro- I ducing appreciable viscosity increase in the original oil and without imparting grease-like characteristics. 13. The oil of claim 12 wherein the soap is calcium soap.

14. An oil according to claim 12 wherein is employed metal soap of acids of the class consisting of sulfurized fatty acids, sulfurized naphthenic acids and sulfurized synthetic petroleum acids. 1

15. An oil accordingv to claim 12 wherein is employed metal soaps of acids of the class consisting of chlorinated fatty acids, chlorinated naphthenic acids and chlorinated synthetic petroleum acids.

16. A normally liquid Diesel engine lubricating oil comprising a viscous mineral lubricating oil containing a small percentage of freely oil-soluble soap of an organic acid having at least about ten carbon atoms per molecule with a filmstrength-increasing agent of the class consisting of halogens, sulfur and phosphorus, the soap being present in amount suflicient to overcome substantially deposit of gummy and vamish-like materials in Diesel engines without producing appreciable viscosity increase in the original oil and without imparting grease-like characteritics. h

17. The oil of claim 16 wherein the soap is a calcium soap and the film-strength agent is chlorine.

18. A lubricating oil according to claim 4 wherein the soap employed is such as not to impart grease-dike characteristics or appreciable increase in the' viscosity of the original oil.

19. A lubricating oil according to claim 5 wherein the soap employed is such as not to impart grease-like characteristics or appreciable increase in the viscosity of the original oil.

20. A lubricating oil according to claim 6 wherein the soap employed is such as not to impart grease-like characteristics or appreciable increase in the viscosity of the original oil and the oil is a non-waxy oil.

21. A lubricating oil according to claim 7 wherein the soap employed is such as not to impart grease-like characteristics or appreciable increase in the viscosity of the original oil.

22. A lubricating oil comprising as primary ingredients a mineral lubricating oil and freely oil-' soluble calcium chloro stearates corresponding generally in chlorine content to calcium dichlorostearates, the oil having increasedoiliness and film strength and anti-ring sticking characteristics by reason of said soap and the quantity of soap present being between about and about 2% and such as not to impart appreciably increased viscosity and grease-like characteristics.

23. A lubricating oil for severe service internal combustion engines comprising a non-waxy mineral lubricating oil of a lubricating viscosity range containing in the order of 1% of a freely oil-soluble metal soap not appreciably increasing the viscosity of the original oil not imparting grease-like characteristics and containing a chemically combined film strength agent of the class consisting of halogens, sulfur and phosphorus.

ULRIC B. BRAY. 

